They're not stuck as in "there are no other options", they're stuck as in "there are cheaper, crappier options but we'd have to pack up our entire lives and deal with the other expenses/headaches that come with moving so I guess we might as well just suffer with the increase". 

In my opinion if you could get the 10-pack in the 600-615 range (assuming due diligence irons out), then they could hit that 10% CoC as-is.

(Let's put up beware of dogs signs and have a pack of dobermans patrolling the grounds.)  

I don't think anyone has ever said anything about sheets, towels, Keurigs, wifi speed, tv stations, pack-n-plays, the games in the game room, the upgraded appliances, etc.

pack your trips with showings and meetings.if it's not worth it to you to spend some time and money doing that... then don't spend tens of thousands of dollars on a property.

AI can't write property descriptions at all and those who use it are going to fall back in the pack because the algorithms can recognize it.

If heat goes out in the winter we drop off several units, so they can be placed in different parts of the house - including every room with water like kitchen and bathrooms.We also have dehumidifiers, carpet blowers, shop vacs, puddle-sucker pumps, extra hoses, extra sump pumps with battery pack, squeegees, and portable AC units ready to deploy. 

You are honestly way ahead of the pack already simply by being willing to start learning about this topic in your early 20s.

As for other amenities, some crowd-pleasers that won't break the bank are coffee maker + starter pack of pods, basic workout equipment (yoga mat, resistance bands), phone charging stations by the beds, and basic kitchen essentials like olive oil, salt/pepper, coffee filters, etc.

Think of it as the rough sketch that helps you figure out where you want to swim: Omaha’s stable single-family rentals with decent cash flow and strong appreciation potential, the sizzling up-and-coming pockets around San Antonio where off-market deals still lurk if you’re willing to roll up your sleeves, or those tight-knit Chicago neighborhoods where a trusted investor-friendly agent can point you to contractors who won’t ghost you mid-reno.